1. Field of the Invention
The present invention relates generally to a boom lift apparatus for use on a truck having a boom and a boom mounted bucket, and relates, more particularly, to a load measurement system and method of measuring the load experienced by a boom lift apparatus during use.
2. Discussion of the Prior Art
It is known from U.S. Pat. No. 4,466,506, issued on Aug. 21, 1984, to Dolenti, to provide a wire lift device for use on a jib of a bucket truck. The lift device includes a mast that is axially received in an adapter having a plurality of guide rollers for permitting relative axial movement of the mast while preventing angular movement thereof. A power winch is typically mounted on the boom of the truck and is connected to a rope or cable that extends between the winch and the bottom end of the mast such that operation of the winch moves the mast in the axial direction between raised and lowered positions.
It is also conventional to provide a load measurement system on known lift devices that is capable of roughly measuring the load experienced by the mast during a lifting operation. In such a conventional system, a spring is attached between the mast and the adapter, and an indicator is provided along with a scale for displaying the amount of deflection of the spring as well as the approximate force exerted on the spring by the load carried by the mast.